The New Mexico Environment Department wants the Department of Energy’s cleanup contractor at the Los Alamos National Laboratory to suspend part of its chromium plume mitigation program over concerns it might force contamination deeper underground, a federal official said Thursday.
In December, the state sent a letter to Michael Mikolanis, DOE’s field boss for the Office of Environmental Management, and contractor Newport News Nuclear BWXT Los Alamos (N3B), Mikolanis said during a lab cleanup presentation. New Mexico wants a halt to injection of clean groundwater “along downgradient side of the plume” by April 1.
The state wants DOE to “cease” injections until one of two things occur, Mikolanis said. Either DOE completes an action plan, which could take two years, or until “we can definitely prove” through modeling and data that “our operations are not causing further migration of the plume.”
The DOE believes the damage to the aquifer occurred years ago when hexavalent chromium was used to clean pipes at a Los Alamos power plant and was released into the environment. The release started around 1972 and was discovered in 2005, according to the DOE contractor.
“Water is going to move no matter what we do,” so a certain degree of plume migration is inevitable until there is a permanent fix, Mikolanis said. The state concern was sparked by abnormal readings at a couple of plume monitoring wells, he added.
In recent years, DOE has used interim measures “to contain the plume on laboratory land while we get a resolution in place,” Mikolanis said. This involves extracting contaminated groundwater, treating it nearby and then reinjecting the treated or clean groundwater underground. Currently the plume is about 500 feet away from the laboratory’s boundary with the Pueblo de San Ildefonso, according to DOE.
“Without the ability to re-inject my ability to treat is significantly impaired,” Mikolanis said. The DOE boss hopes an “amicable” solution is reached with the state.
Last year DOE extracted over 100 million gallons and treated it, successfully removing 156 pounds of chromium 6 from the water.
